8303930: Fix ConstantUtils.skipOverFieldSignature void case return value

Reviewed-by: mchung

Author: liach

src/java.base/share/classes/java/lang/constant/ConstantUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -193,7 +193,7 @@ static int skipOverFieldSignature(String descriptor, int start, int end, boolean
         int index = start;
         while (index < end) {
             switch (descriptor.charAt(index)) {
-                case JVM_SIGNATURE_VOID: if (!voidOK) { return index; }
+                case JVM_SIGNATURE_VOID: if (!voidOK) { return 0; }
                 case JVM_SIGNATURE_BOOLEAN:
                 case JVM_SIGNATURE_BYTE:
                 case JVM_SIGNATURE_CHAR:

test/jdk/java/lang/constant/boottest/java.base/java/lang/constant/ConstantUtilsTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -33,6 +33,7 @@
 
 /**
  * @test
+ * @bug 8303930
  * @compile ConstantUtilsTest.java
  * @run testng ConstantUtilsTest
  * @summary unit tests for methods of java.lang.constant.ConstantUtils that are not covered by other unit tests
@@ -66,4 +67,9 @@ public void testValidateMemberName() {
             }
         }
     }
+
+    public void testSkipOverFieldSignatureVoid() {
+       int ret = ConstantUtils.skipOverFieldSignature("(V)V", 1, 4, false);
+       assertEquals(ret, 0, "Descriptor of (V)V starting at index 1, void disallowed");
+    }
 }